title: Myofibroblasts and colonic anastomosis healing in Wistar rats.
abstract: BACKGROUND
  The myofibroblasts play a central role in wound healing throughout the body. The process of wound healing in the colon was evaluated with emphasis on the role of myofibroblasts.
  
  
  METHODS
  One hundred male Wistar rats weighing 274 ± 9.1 g (mean age: 3.5 months) were used. A left colonic segment was transected and the colon was re-anastomosed. Animals were randomly divided into two groups. The first group experimental animals (n = 50) were sacrificed on postoperative day 3, while the second group rats (n = 50) were sacrificed on postoperative day 7. Healing of colonic anastomosis was studied in terms of anastomotic bursting pressure, as well as myofibroblastic reaction and expression of α-smooth muscle actin (α-SMA), adhesion formation, inflammatory reaction and neovascularization.
  
  
  RESULTS
  The mean anastomotic bursting pressure increased from 20.6 ± 3.5 mmHg on the 3rd postoperative day to 148.8 ± 9.6 Hg on the 7th postoperative day. Adhesion formation was increased on the 7th day, as compared to the 3rd day. In addition, the myofibroblastic reaction was more profound on the 7th postoperative day in comparison with the 3rd postoperative day. The staining intensity for α-SMA was progressive from the 3rd to the 7th postoperative day. On the 7th day the α-SMA staining in the myofibroblats reached the level of muscular layer cells.
  
  
  CONCLUSIONS
  Our study emphasizes the pivotal role of myofibroblasts in the process of colonic anastomosis healing. The findings provide an explanation for the reduction in the incidence of wound dehiscence after the 7th postoperative day.
authors.affiliation: A' Propedeutic Surgical Clinic, Aristotle University Medical School, AHEPA Hospital, Thessaloniki, Greece. dr.ckosmidis@gmail.com
authors.forename: Christophoros
authors.initials: C
authors.lastname: Kosmidis
authors.forename: Christoforos
authors.initials: C
authors.lastname: Efthimiadis
authors.forename: Georgios
authors.initials: G
authors.lastname: Anthimidis
authors.forename: George
authors.initials: G
authors.lastname: Basdanis
authors.forename: Stylianos
authors.initials: S
authors.lastname: Apostolidis
authors.forename: Prodromos
authors.initials: P
authors.lastname: Hytiroglou
authors.forename: Kalliopi
authors.initials: K
authors.lastname: Vasiliadou
authors.forename: John
authors.initials: J
authors.lastname: Prousalidis
authors.forename: Epameinondas
authors.initials: E
authors.lastname: Fahantidis
mesh_terms: D000199:Actins / Q000096:biosynthesis; D000714:Anastomosis, Surgical; D000818:Animals; D003106:Colon / Q000098:blood supply / Q000601:surgery*; D006874:Hydrostatic Pressure; D007249:Inflammation; D008297:Male; D058628:Myofibroblasts / Q000378:metabolism*; D018919:Neovascularization, Physiologic; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D000267:Tissue Adhesions; D014945:Wound Healing / Q000502:physiology*
chemical_list: D000199:Actins; C498862:Acta2 protein, rat